/*
 * tcp.cpp
 *
 *  Created on: Oct 12, 2011
 *      Author: welcome
 */
#include <KD/kd.h>
#include <tcp.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netdb.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <errno.h>
#include <string.h>
#include <sys/select.h>
#include <ui.h>

#ifndef INADDR_NONE
#define INADDR_NONE ((unsigned long) -1)
#endif

#ifdef WITH_SCARD
#define STREAM_COUNT 8
#else
#define STREAM_COUNT 1
#endif

#define TCP_CLOSE(_sck) close(_sck)
#define TCP_STRERROR strerror(errno)
#define TCP_BLOCKS (errno == EWOULDBLOCK)

static int g_sock;
static struct stream g_in;
static struct stream g_out[STREAM_COUNT];
int g_tcp_port_rdp = TCP_PORT_RDP;
extern RD_BOOL g_user_quit;

/* wait till socket is ready to write or timeout */
static RD_BOOL tcp_can_send(int sck, int millis) {
	fd_set wfds;
	struct timeval time;
	int sel_count;

	time.tv_sec = millis / 1000;
	time.tv_usec = (millis * 1000) % 1000000;
	FD_ZERO(&wfds);
	FD_SET(sck, &wfds);
	sel_count = select(sck + 1, 0, &wfds, 0, &time);
	if (sel_count > 0) {
		return True;
	}
	return False;
}

/* Initialise TCP transport data packet */
STREAM tcp_init(uint32 maxlen) {
	static int cur_stream_id = 0;
	STREAM result = NULL;

#ifdef WITH_SCARD
	scard_lock(SCARD_LOCK_TCP);
#endif
	result = &g_out[cur_stream_id];
	cur_stream_id = (cur_stream_id + 1) % STREAM_COUNT;

	if (maxlen > result->size) {
		result->data = (uint8 *) kdRealloc(result->data, maxlen);
		result->size = maxlen;
	}

	result->p = result->data;
	result->end = result->data + result->size;
#ifdef WITH_SCARD
	scard_unlock(SCARD_LOCK_TCP);
#endif
	return result;
}

/* Send TCP transport data packet */
void tcp_send(STREAM s) {
	int length = s->end - s->data;
	int sent, total = 0;

#ifdef WITH_SCARD
	scard_lock(SCARD_LOCK_TCP);
#endif
	while (total < length) {
		sent = send(g_sock, s->data + total, length - total, 0);
		if (sent <= 0) {
			if (sent == -1 && TCP_BLOCKS) {
				tcp_can_send(g_sock, 100);
				sent = 0;
			} else {
				error("send: %s\n", TCP_STRERROR);
				return;
			}
		}
		total += sent;
	}
#ifdef WITH_SCARD
	scard_unlock(SCARD_LOCK_TCP);
#endif
}

/* Receive a message on the TCP layer */
STREAM tcp_recv(STREAM s, uint32 length) {
	uint32 new_length, end_offset, p_offset;
	int rcvd = 0;

	if (s == NULL) {
		/* read into "new" stream */
		if (length > g_in.size) {
			g_in.data = (uint8 *) kdRealloc(g_in.data, length);
			g_in.size = length;
		}
		g_in.end = g_in.p = g_in.data;
		s = &g_in;
	} else {
		/* append to existing stream */
		new_length = (s->end - s->data) + length;
		if (new_length > s->size) {
			p_offset = s->p - s->data;
			end_offset = s->end - s->data;
			s->data = (uint8 *) kdRealloc(s->data, new_length);
			s->size = new_length;
			s->p = s->data + p_offset;
			s->end = s->data + end_offset;
		}
	}

	while (length > 0) {
		if (!ui_select(g_sock)) {
			/* User quit */
			g_user_quit = True;
			return NULL;
		}
		rcvd = recv(g_sock, s->end, length, 0);
		if (rcvd < 0) {
			if (rcvd == -1 && TCP_BLOCKS) {
				rcvd = 0;
			} else {
				error("recv: %s\n", TCP_STRERROR);
				return NULL;
			}
		} else if (rcvd == 0) {
			error("Connection closed\n");
			return NULL;
		}

		s->end += rcvd;
		length -= rcvd;
	}
	return s;
}

/* Establish a connection on the TCP layer */
RD_BOOL tcp_connect(char *server) {
	socklen_t option_len;
	uint32 option_value;
	int i;

#ifdef IPv6

	int n;
	struct addrinfo hints, *res, *ressave;
	char tcp_port_rdp_s[10];

	snprintf(tcp_port_rdp_s, 10, "%d", g_tcp_port_rdp);

	memset(&hints, 0, sizeof(struct addrinfo));
	hints.ai_family = AF_UNSPEC;
	hints.ai_socktype = SOCK_STREAM;

	if ((n = getaddrinfo(server, tcp_port_rdp_s, &hints, &res)))
	{
		error("getaddrinfo: %s\n", gai_strerror(n));
		return False;
	}

	ressave = res;
	g_sock = -1;
	while (res)
	{
		g_sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
		if (!(g_sock < 0))
		{
			if (connect(g_sock, res->ai_addr, res->ai_addrlen) == 0)
			break;
			TCP_CLOSE(g_sock);
			g_sock = -1;
		}
		res = res->ai_next;
	}
	freeaddrinfo(ressave);

	if (g_sock == -1)
	{
		error("%s: unable to connect\n", server);
		return False;
	}

#else /* no IPv6 support */

	struct hostent *nslookup;
	struct sockaddr_in servaddr;
	KDuint32 s_addr;

//	inet_pton(AF_INET, server, &servaddr);

	if ((nslookup = gethostbyname(server)) != NULL) {
		memcpy(&servaddr.sin_addr, nslookup->h_addr, sizeof(servaddr.sin_addr));
	}else if (0 == kdInetAton(server, &s_addr)){
		servaddr.sin_addr.s_addr = INADDR_NONE;
		error("%s: unable to resolve host\n", server);
		return False;
	}else{
		servaddr.sin_addr.s_addr = s_addr;
	}
	if ((g_sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
		error("socket: %s\n", TCP_STRERROR);
		return False;
	}
	servaddr.sin_family = AF_INET;
	servaddr.sin_port = kdHtons((uint16) g_tcp_port_rdp);

	if (connect(g_sock, (struct sockaddr *) &servaddr, sizeof(struct sockaddr))
			< 0) {
		error("connect: %s\n", TCP_STRERROR);
		TCP_CLOSE(g_sock);
		return False;
	}

#endif /* IPv6 */

	option_value = 1;
	option_len = sizeof(option_value);
	setsockopt(g_sock, IPPROTO_TCP, TCP_NODELAY, (void *) &option_value,
			option_len);
	/* receive buffer must be a least 16 K */
	if (getsockopt(g_sock, SOL_SOCKET, SO_RCVBUF, (void *) &option_value,
			&option_len) == 0) {
		if (option_value < (1024 * 16)) {
			option_value = 1024 * 16;
			option_len = sizeof(option_value);
			setsockopt(g_sock, SOL_SOCKET, SO_RCVBUF, (void *) &option_value,
					option_len);
		}
	}

	g_in.size = 4096;
	g_in.data = (uint8 *) kdMalloc(g_in.size);

	for (i = 0; i < STREAM_COUNT; i++) {
		g_out[i].size = 4096;
		g_out[i].data = (uint8 *) kdMalloc(g_out[i].size);
	}

	return True;
}

/* Disconnect on the TCP layer */
void tcp_disconnect(void) {
	TCP_CLOSE(g_sock);
}

char *
tcp_get_address() {
	static char ipaddr[32];
	struct sockaddr_in sockaddr;
	socklen_t len = sizeof(sockaddr);
	if (getsockname(g_sock, (struct sockaddr *) &sockaddr, &len) == 0) {
		uint8 *ip = (uint8 *) &sockaddr.sin_addr;
		sprintf(ipaddr, "%d.%d.%d.%d", ip[0], ip[1], ip[2], ip[3]);
	} else
		strcpy(ipaddr, "127.0.0.1");
	return ipaddr;
}

/* reset the state of the tcp layer */
/* Support for Session Directory */
void tcp_reset_state(void) {
	int i;

	g_sock = -1; /* reset socket */

	/* Clear the incoming stream */
	if (g_in.data != NULL)
		kdFree(g_in.data);
	g_in.p = NULL;
	g_in.end = NULL;
	g_in.data = NULL;
	g_in.size = 0;
	g_in.iso_hdr = NULL;
	g_in.mcs_hdr = NULL;
	g_in.sec_hdr = NULL;
	g_in.rdp_hdr = NULL;
	g_in.channel_hdr = NULL;

	/* Clear the outgoing stream(s) */
	for (i = 0; i < STREAM_COUNT; i++) {
		if (g_out[i].data != NULL)
			kdFree(g_out[i].data);
		g_out[i].p = NULL;
		g_out[i].end = NULL;
		g_out[i].data = NULL;
		g_out[i].size = 0;
		g_out[i].iso_hdr = NULL;
		g_out[i].mcs_hdr = NULL;
		g_out[i].sec_hdr = NULL;
		g_out[i].rdp_hdr = NULL;
		g_out[i].channel_hdr = NULL;
	}
}
